diy overflow gph?

[skratchiechan]

so I'm making a u tube style overflow
DIY Overflow Box (DIY OVERFLOW PROJECTS)

and was wondering how much water is going thru this box? if any of you guys/gals made this overflow box before...

I wanna make sure I get the right return pump for it

 

[melosu58]

Moved to the DIY forum.

 

[David S]

cant say for sure but hazard a guess at max of 500-600gph,you'd need the compare with a manufactured one using 3/4 tube.I wouldn't bother with the holes either,too easy to get blocked just cut slots,how much will this cost to build compared to buy,eshopps are good.what are you going to use as the u tube.plus the nipple on the top I wouldn't trust.On mine to start off syphon I just push some air line up the tube and sucked out the air,any left in there should be forced out with the flow.I did this when first installed months ago.I also wouldn't bother with the 3/4 barb fitting just go larger( 1 1/2"pipe and bends)that way if you want to up the flow just add another u tube